Review article: pharmacological therapy for hepatocellular carcinoma with sorafenib and other oral agents

Differences in the pharmacokinetics and steady-state blood concentrations of orally administered lenvatinib in adult and juvenile rats

Objective: The aim of this study was to compare the pharmacokinetics and steady-state serum concentrations of lenvatinib in adult and juvenile rats. Experimental study: An ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) method was developed to quantify lenvatinib in the serum and liver of rats. Six juvenile and six adult rats in each group were orally administered with a single dose of 7.0 mg/kg lenvatinib suspension for pharmacokinetics. Another 12 juvenile and adult rats were subjected to oral gavage with 7.0 mg/kg lenvatinib once daily for 5 days. Biofluild samples were pre-treated by protein precipitation and sorafenib was used as the internal standard for UPLC-MS analysis. The pharmacokinetic parameters were estimated by compartment and statistical model. The mRNA expression of CYP3A2 and SLC22A1 in liver of adult and juvenile rats was measured by real-time fluorescence quantitative PCR (RT-qPCR). Results: The UPLC-MS method met the requirements for quantitative analysis of lenvatinib in serum and liver. The pharmacokinetic results showed that the mean retention time (MRT(0-∞)) was 19.64 ± 7.64 h and 126.38 ± 130.18 h, with AUC(0-∞) values of 3.97 ± 0.73 μg‧mL-1 h and 5.95 ± 2.27 μg mL-1 h in adult and juvenile rats, respectively. When comparing adult rats (0.35 ± 0.15 μg/mL) to juvenile rats, no significant differences were observed in steady-state serum lenvatinib (0.32 ± 0.11 μg/mL), but a noteworthy decrease to one-third of steady-state liver lenvatinib was observed after multiple oral doses of lenvatinib in juvenile rats. Additional findings revealed that the mRNA expression of CYP3A2 and SLC22A1 was notably increased by 6.86 and 14.67 times, respectively, in juvenile rats compared to adult rats. Conclusion: Juvenile rats exhibit lower levels of lenvatinib in the liver's steady-state, potentially due to the disparity in CYP3A2 mRNA expression. These results imply that the dosage of lenvatinib for pediatric patients may need to be augmented in order to attain the desired clinical outcome.

Rescuing SLAMF3 Expression Restores Sorafenib Response in Hepatocellular Carcinoma Cells through the Induction of Mesenchymal-to-Epithelial Transition

Background: Acquired resistance to sorafenib in hepatocellular carcinoma (HCC) patients results in poor prognosis. Epithelial-to-mesenchymal transition (EMT) is the major mechanism implicated in the resistance to sorafenib. We have reported the tumor suppressor role of SLAMF3 (signaling lymphocytic activation molecules family 3) in HCC progression and highlighted its implication in controlling the MRP-1 transporter activity. These data suggest the implication of SLAMF3 in sorafenib resistance mechanisms. Methods: We evaluated the resistance to sorafenib in Huh-7 cells treated with progressive doses (Res cells). We investigated the link between acquired resistance to sorafenib and SLAMF3 expression by flow cytometry and Western blot methods. Furthermore, we analyzed the EMT and the stem cell potential of cells resistant to sorafenib. Results: Sorafenib resistance was confirmed in Res cells by analyzing the cell viability in the presence of sorafenib. The mesenchymal transition, in Res cells, was confirmed by high migratory index and the expression of EMT antigens. Interestingly, we found that loss of SLAMF3 expression corresponded to sorafenib-resistant phenotypes. The overexpression of SLAMF3 reversed EMT, decreased metastatic potential and inhibited mTOR/ERK1/2 in Res cells. Conclusions: We propose that rescuing SLAMF3 expression in resistant cells could represent a potential therapeutic strategy to enhance sorafenib efficacy in HCC patients.

Radioembolization vs sorafenib in locally advanced hepatocellular carcinoma with portal vein tumor thrombosis: A propensity score and Bayesian analysis

OBJECTIVE

In this study we aimed to compare patient outcomes between the use of transarterial radioembolization (TARE) and sorafenib in patients with hepatocellular carcinoma (HCC) and intrahepatic portal vein tumor thrombosis (PVTT).

METHODS

A total of 65 patients with HCC and intrahepatic PVTT treated in five Italian hospitals between 2012 and 2018 were included in the analysis. Those with any previous treatment, extension of PVTT to the main portal tract and extrahepatic involvement were excluded. Propensity score matching analysis and Bayesian model averaging analysis were performed.

RESULTS

Of the 41 patients treated with TARE and 24 with sorafenib, 11 patients were downstaged to curative-intent surgery (liver transplant in three and hepatectomy in eight), including 10 treated with TARE and one with sorafenib. TARE was more effective than sorafenib in downstaging patients to surgery, achieving a mean survival of 54 months. In the 54 patients without downstaging after treatment, of whom 31 were treated with TARE and 23 with sorafenib, median survival was 20.3 and 9.1 months, respectively (P = 0.001), with different 1-, 2- and 3-year OS rates (64.5%, 42.6% and 37.3% vs 39.1%, 13.0% and 0%). Both propensity score and Bayesian model averaging confirmed an improvement in overall survival in the TARE group compared with sorafenib treatment.

CONCLUSIONS

TARE was more effective than sorafenib in downstaging patients with HCC to surgery, providing a significant improvement in survival. Even in patients who were not downstaged to surgery, survival appeared to be superior with TARE over sorafenib.

Computationally guided high-throughput design of self-assembling drug nanoparticles

Nanoformulations of therapeutic drugs are transforming our ability to effectively deliver and treat a myriad of conditions. Often, however, they are complex to produce and exhibit low drug loading, except for nanoparticles formed via co-assembly of drugs and small molecular dyes, which display drug-loading capacities of up to 95%. There is currently no understanding of which of the millions of small-molecule combinations can result in the formation of these nanoparticles. Here we report the integration of machine learning with high-throughput experimentation to enable the rapid and large-scale identification of such nanoformulations. We identified 100 self-assembling drug nanoparticles from 2.1 million pairings, each including one of 788 candidate drugs and one of 2,686 approved excipients. We further characterized two nanoparticles, sorafenib-glycyrrhizin and terbinafine-taurocholic acid both ex vivo and in vivo. We anticipate that our platform can accelerate the development of safer and more efficacious nanoformulations with high drug-loading capacities for a wide range of therapeutics.

LINC00978 promotes hepatocellular carcinoma carcinogenesis partly via activating the MAPK/ERK pathway

Objective: To study the role of long non-coding RNA (lncRNA) LINC00978 in hepatocellular carcinoma (HCC) carcinogenesis.

Materials and methods: LINC00978 expression level was measured by reverse transcription quantitative real-time PCR (RT-qPCR) in HCC tissues and adjacent healthy liver tissues from 49 HCC patients. MTT assay, colony forming assay, and flow cytometry were performed to evaluate the effects of shRNA-mediated LINC00978 knockdown on HCC cell proliferation, cell cycle progression, and apoptosis in vitro. Xenograft tumor model was performed to determine the effects of LINC00978 knockdown on HCC tumor growth in vivo. Western blot was used to assess the activation of signaling molecules in the apoptosis and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathway.

Results: LINC00978 expression was significantly up-regulated in human HCC tissue relative to adjacent normal tissue, and LINC00978 high expression was correlated with poor HCC overall survival. LINC00978 was up-regulated in HCC cell lines. ShRNA-mediated LINC00978 knockdown significantly decreased HCC cell proliferation, and induced HCC cell cycle arrest and apoptosis in vitro. LINC00978 knockdown led to significant decrease in tumor xenograft size in vivo. Western blots revealed LINC00978 inhibition decreased ERK, p38, and c-Jun N-terminal kinase (JNK) phosphorylation in HCC cells.

Conclusions: LINC00978 is highly expressed in human HCC tissue and correlates with poor HCC prognosis. LINC00978 promotes HCC cell proliferation, cell cycle progression, and survival, partially by activating the MAPK/ERK pathway. Our findings partially elucidated the roles of LINC00978 in HCC carcinogenesis, and identified a therapeutic target for HCC.

Effect of Combined Sorafenib/Cisplatinum Treatment on the Autophagy and Proliferation of Hepatocellular Carcinoma hepG2 Cells in Vitro

Objective:

To explore the effect of combined Sorafenib/ cisplatinum treatment on the autophagy and proliferation of hepatocellular carcinoma (HepG2) cells in vitro.

Methods:

HepG2 cells were cultured and treated with different concentrations of Sorafenib, cisplatinum, or a combination of both over a 24-hour period. Cell proliferation was evaluated using a CCK8 assay, and the mRNA expression of the autophagy-related proteins AKT, mTOR, and LC3 were detected using quantitative PCR (qPCR). AKT, pAKT (Ser473), mTOR, pmTOR (Ser2448), LC3I, and LC3II protein expression levels were evaluated by western blot.

Results:

We found that the survival rate of HepG2 cells was 47.42% when treated with Sorafenib (10 μmol/L) monotherapy, and 46.04% when treated with cisplatinum (10 mg/L) monotherapy. When Sorafenib(10 μmol/L) was combined with cisplatinum (10 mg/L), the cellular proliferation and survival rate was only 16.71% ( P <0.05). qPCR and western blot revealed that a combination of Sorafenib (10 μmol/L) and cisplatinum (10 mg/L) reduced the transcription and protein expression of autophagy-related AKT and mTOR but increased that of LC3 (P <0.05).

Conclusion:

Combining Sorafenib and cisplatinum can effectively induce cell autophagy and reduce cellular proliferation via the PI3K/AKT/mTOR signal pathway.

Diabetes and hepatocellular carcinoma: A pathophysiological link and pharmacological management

Both diabetes mellitus (DM) and cancer are multifarious, dissimilar, and long-lasting, fatal diseases with a remarkable influence on health worldwide. DM is not only related to cardiovascular diseases, neuropathy, nephropathy, and retinopathy, but also related to a number of liver diseases such as nonalcoholic fatty liver disease, steatohepatitis, and liver cirrhosis. Recently, it is hypothesized that DM has a greater risk for many forms of cancer, such as breast, colorectal, endometrial, pancreatic, gallbladder, renal, and liver cancer including hepatocellular carcinoma (HCC). Both DM and cancer have many common risk factors, but the association between these two is poorly stated. Several epidemiologic studies have revealed the association between pathogenic and prognostic characteristics of DM and a higher incidence of HCC, thus representing DM as an independent risk factor for HCC development. The etiological and pathophysiological relationship between DM and HCC has been presented in this review by linking hyperglycemia, hyperinsulinemia, insulin resistance, and activation of insulin-like growth factor signaling pathways and pharmacological management of HCC associated with DM.

Targeting human liver cancer cells with lactobionic acid-G(4)-PAMAM-FITC sorafenib loaded dendrimers

Reported here is the synthesis and biological evaluation of the asialoglycoprotein receptor (ASGP-R) targeted fourth generation poliamidoamine dendrimer (G(4)-PAMAM) loaded with sorafenib. The ASGP-R targeted dendrimer was obtained by conjugation of Lactobionic acid (La) to the G(4)-PAMAM dendrimer, followed by acetylation (Ac) of the free amino groups in order to reduce the non-specific interactions with the cell membrane. Moreover, by additionally grafting fluorescein (FITC), it was easy to characterize the internalization pathway and the intracellular fate of the targeted dendrimer Ac-La-G(4)-PAMAM-FITC. In vitro experiments performed on HepG-2 and HLE cell lines, allowed to study the ability of the dendrimers to affect the cell vitality. Confocal microscopy and cytofluorimetric analysis confirmed higher binding and uptake ability of the Ac-La-G(4)-PAMAM-FITC dendrimer in well differentiated and ASGP-R expressing human liver cancer cell line HepG-2 compared non-expressing HLE cells. Ac-La-G(4)-PAMAM-FITC dendrimer loaded with sorafenib was stable and showed sustained sorafenib release. As evidenced by the cytotoxicity studies, sorafenib included in the dendrimer maintained its effectiveness, and was able to produce a longer lasting effect over the time compared to molar equivalent doses of free sorafenib. This new targeted dendrimer appears to be a suitable carrier for the delivery of sorafenib to liver cancer cells expressing ASGP-R.

Animal models as a tool in hepatocellular carcinoma research: A Review

Cancer is the first cause of death in developed countries and the second in developing countries. Concerning the most frequent worldwide-diagnosed cancer, primary liver cancer represents approximately 4% of all new cancer cases diagnosed globally. However, among primary liver cancer, hepatocellular carcinoma is by far the most common histological subtype. Notwithstanding the health promotion and disease prevention campaigns, more than half a million new hepatocellular carcinoma cases are reported yearly, being estimated to growth continuously until 2020. Taking this scenario under consideration and the fact that some aspects concerning hepatocellular carcinoma evolution and metastasize process are still unknown, animal models assume a crucial role to understand this disease. The animal models have also provided the opportunity to screen new therapeutic strategies. The present review was supported on research and review papers aiming the complexity and often neglected chemically induced animal models in hepatocarcinogenesis research. Despite the ongoing debate, chemically induced animal models, namely, mice and rat, can provide unique valuable information on the biotransformation mechanisms against xenobiotics and apprehend the deleterious effects on DNA and cell proteins leading to carcinogenic development. In addition, taking under consideration that no model achieves all hepatocellular carcinoma research purposes, criteria to define the " ideal" animal model, depending on the researchers' approach, are also discussed in this review.

HBx sensitizes hepatocellular carcinoma cells to lapatinib by up-regulating ErbB3

Poor prognosis of hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC) involves HBV X protein (HBx)-induced tumor progression. HBx also contributes to chemo-resistance via inducing the expressions of anti-apoptosis and multiple drug resistance genes. However, the impact of HBx expression on the therapeutic efficacy of various receptor tyrosine kinase inhibitors remains unknown. In this study, our data showed that HBx overexpression did not alter the cellular sensitivity of HCC cell lines to sorafenib but unexpectedly enhanced the cell death induced by EGFR family inhibitors, including gefitinib, erlotinib, and lapatinib due to ErbB3 up-regulation. Mechanistically, HBx transcriptionally up-regulates ErbB3 expression in a NF-κB dependent manner. In addition, HBx also physically interacts with ErbB2 and ErbB3 proteins and enhances the formation of ErbB2/ErbB3 heterodimeric complex. The cell viability of HBx-overexpressing cells was decreased by silencing ErbB3 expression, further revealing the pivotal role of ErbB3 in HBx-mediated cell survival. Our data suggest that HBx shifts the oncogenic addiction of HCC cells to ErbB2/ErbB3 signaling pathway via inducing ErbB3 expression and thereby enhances their sensitivity to EGFR/ErbB2 inhibitors.

Rosuvastatin as a potential preventive drug for the development of hepatocellular carcinoma associated with non-alcoholic fatty liver disease in mice

Hepatocellular carcinoma (HCC) represents approximately 85% of all primary liver cancer cases. Non-alcoholic fatty liver disease (NAFLD) is one of the risk factors for HCC. NAFLD occurs in patients with components of metabolic syndrome, such as type 2 diabetes mellitus, obesity, hypertension and hyperlipidemia. Therefore, hyperlipidemia also represents a patient population at risk for HCC that can readily be identified. Rosuvastatin, a 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitor, has exhibited a more potent affinity for the active site of HMG-CoA reductase than other statins. In addition, the hepatic uptake of rosuvastatin in rats has been found to be more selective and efficient than that with other drugs. Furthermore, the cytoprotective effects of rosuvastatin against ischemic injury have been clearly reported. Thus, in this study, we aimed to determine the role of rosuvastatin as a preventive drug in HCC associated with NAFLD. STAM mice, which developed HCC from NAFLD by being fed a high-fat diet (HFD), were divided into a group in which a HFD was given to the mice for 15 weeks (n=8) and another in which a HFD supplemented with 0.00125% rosuvastatin was given to the mice for 15 weeks (n=8). Rosuvastatin inhibited the development of hepatic tumors in the mice with NAFLD induced by a specific diet both macroscopically and histologically. Rosuvastatin significantly decreased the expression levels of pro-inflammatry cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-6 and transforming growth factor (TGF)-β1. Tumor aggressiveness is mediated by angiogenic factors. Therefore, we examined the hepatic mRNA expression of vascular endothelial growth factor receptor (VEGFR), epidermal growth factor receptor (EGFR) and platelet-derived growth factor (PDGF). The hepatic expression of these factors significantly decreased in the rousvastin-fed mice. Our results thus suggest rosuvastatin that prevents carcinogenesis and improves the hepatic background. Our data suggest that rosuvastatin has potential for use as a preventive drug for the development of HCC associated with NAFLD in mice.

Single Agent and Synergistic Activity of the "First-in-Class" Dual PI3K/BRD4 Inhibitor SF1126 with Sorafenib in Hepatocellular Carcinoma

Deregulated PI3K/AKT/mTOR, Ras/Raf/MAPK, and c-Myc signaling pathways are of prognostic significance in hepatocellular carcinoma (HCC). Sorafenib, the only drug clinically approved for patients with advanced HCC, blocks the Ras/Raf/MAPK pathway but it does not inhibit the PI3K/AKT/mTOR pathway or c-Myc activation. Hence, there is an unmet medical need to identify potent PI3K/BRD4 inhibitors, which can be used either alone or in combination with sorafenib to treat patients with advanced HCC. Herein, we show that SF1126 (pan PI3K/BRD4 inhibitor) as single agent or in combination with sorafenib inhibited proliferation, cell cycle, apoptosis, and multiple key enzymes in PI3K/AKT/mTOR and Ras/Raf/MAPK pathway in Hep3B, HepG2, SK-Hep1, and Huh7 HCC cell lines. We demonstrate that the active moiety of the SF1126 prodrug LY294002 binds to and blocks BRD4 interaction with the acetylated histone-H4 chromatin mark protein and displaced BRD4 coactivator protein from the transcriptional start site of MYC in Huh7 and SK-Hep1 HCC cell lines. Moreover, SF1126 blocked expression levels of c-Myc in HCC cells. Treatment of SF1126 either alone or in combination with sorafenib showed significant antitumor activity in vivo Our results establish that SF1126 is a dual PI3K/BRD4 inhibitor. This agent has completed a phase I clinical trial in humans with good safety profile. Our data support the potential future consideration of a phase II clinical trial of SF1126, a clinically relevant dual "first-in-class" PI3K/BRD4 inhibitor in advanced HCC, and a potential combination with sorafenib. Mol Cancer Ther; 15(11); 2553-62. ©2016 AACR.

Synthesis and biological evaluation of matrine derivatives as anti-hepatocellular cancer agents

We delineate herein the synthesis and anti-cancer effects of 15 matrine derivatives. The in vitro growth inhibitory assays showed that most of the prepared compounds exhibited improved anti-proliferative activities towards cancer cells with IC50 17-109 times lower than that of matrine. Compounds CH6 showed the most potent anti-proliferative activities in the four tested cancer cell lines. Moreover, compound CH6 could induce G1 cell cycle arrest and inhibit cell migration in human hepatocellular cancer cell lines Bel-7402 and HepG2 through up-regulation of P21, P27 and E-cadherin and down-regulation of N-cadherin.

Development of inCVAX, In situ Cancer Vaccine, and Its Immune Response in Mice with Hepatocellular Cancer

Manipulation of immune system toward the rejection of established cancers has become the standard of care in some patients. Here we propose the development of an in situ autologous cancer vaccine, inCVAX, for the treatment of hepatocellular cancer (HCC). inCVAX is based on the induction of local immunogenic cancer cell death combined with local dendritic cell stimulation by intratumoral injection of the immune-activator N-dihydro-galacto-chitosan (GC). In a first set of experiments, cellular and molecular studies were performed to investigate the effect of inCVAX on immune activation in a murine model of HCC that we previously developed. Once large tumors were formed in mice, the tumor is surgically exposed and a laser fiber was inserted into the center of an individual tumor mass. Using a 10 mm diffuser tip, laser irradiation of 1.5 W was applied to heat the tumor at different durations (6-10 min) to assess tolerability of photothermal application at different temperatures. The laser application was followed by immediate injection of GC, and each mouse received one laser treatment and one GC injection. ELISA was used to assess the level of cytokines; immunohistochemical staining was conducted to analyze the effect of inCVAX on immune cell tumor-filtration and expression of tumor-specific antigens (TSAs) and tumor-associated antigens (TAAs). Results indicate that survival correlated to thermal exposure. At lower temperatures the photothermal effect was sufficient to induce tumor necrosis, but without obvious complication to the mice, although at these temperatures the treatment didn’t alter the level of TSAs and TAAs, so further optimization is suggested. Nevertheless, in response to the inCVAX treatment, cytotoxic cytokine IFN-γ was significantly increased, but suppressive cytokine TGF-β was dramatically reduced. Furthermore, inCVAX prompted tumor infiltration of CD3⁺, CD4⁺, and CD8⁺ T cells; but modulated macrophage subsets differently. In conclusion, while the protocol needs further optimization, it would appear that inCVAX for the treatment of HCC activates an immune response in tumor-bearing mice, which in turn may have potential for the treatment of HCC.

A novel all-trans retinoic acid derivative 4-amino‑2‑trifluoromethyl-phenyl retinate inhibits the proliferation of human hepatocellular carcinoma HepG2 cells by inducing G0/G1 cell cycle arrest and apoptosis via upregulation of p53 and ASPP1 and downregulation of iASPP

4-Amino-2-trifluoromethyl-phenyl retinate (ATPR), a novel all-trans retinoic acid (ATRA) derivative, was reported to function as a tumor inhibitor in various types of cancer cells in vitro. However, little is known concerning its antitumor effect on human hepatocellular carcinoma (HCC) HepG2 cells. The aims of the present study were to investigate the effects of ATPR on the proliferation of HepG2 cells and to explore the probable mechanisms. A series of experiments were performed following the treatment of HepG2 cells with ATRA and ATPR. MTT and plate colony formation assays were used to measure the cell viability. To confirm the influence on proliferation, flow cytometry was used to detect the distribution of the cell cycle. Apoptosis was observed by Hoechst staining and flow cytometry. In addition, to characterize the underlying molecular mechanisms, immunofluorescence was applied to observe the distribution of p53. The transcription and translation levels of p53 were analyzed by real-time quantitative RT-PCR (qRT-PCR) and western blotting. The expression levels of murine double minute 2 (MDM2), apoptosis stimulating proteins of p53 (ASPP), cell cycle- and apoptosis-associated proteins were detected by western blotting. After HepG2 cells were incubated with ATRA and ATPR, the viability of the HepG2 cells was inhibited in a dose- and time-dependent manner. As well, ATPR significantly suppressed HepG2 cell colony formation and arrested cells at the G0/G1 phase, while ATRA had no obvious effects. Both Hoechst staining and flow cytometry unveiled the apoptosis of HepG2 cells. Moreover, the fluorescent density of p53 was higher in the nuclei after exposure to ATPR than that in the ATRA group. HepG2 cells treated with ATPR showed elevated mRNA and protein levels of p53 when compared with these levels in the ATRA-treated cells. Western blotting showed that ATPR increased ASPP1, p21 and Bax expression and decreased MDM2, iASPP, cyclin D and E, cyclin-dependent kinase 6 (CDK6) and Bcl-2 expression, while CDK4 and ASPP2 expression were scarcely altered. Consequently, ATPR exerted a better inhibitory effect on the proliferation of HepG2 cells than ATRA through increased expression of p53 and ASPP1 and downregulation of iASPP, thereby resulting in G0/G1 cell cycle arrest and apoptosis.

Potential of Radiofrequency Ablation in Combination with Immunotherapy in the Treatment of Hepatocellular Carcinoma

Radiofrequency ablation (RFA) is an important treatment option for patients with early hepatocellular carcinoma (HCC). RFA offers a reliable, reproducible modality to effectively treat hepatic lesions with minimal collateral damage to the surrounding hepatic parenchyma. In addition to traditional open operative techniques, RFA can be performed percutaneously or laparoscopically to minimize the physiologic insult to the patient. Due to the concomitant hepatic damage and dysfunction that often is present in patients with HCC these factors make RFA a frequently utilized therapeutic option. However, RFA is most efficacious in treating smaller tumors (≤ 2 cm), particularly when an ablation margin of ≥ 4-5 mm can be obtained. RFA has diminishing utility in larger tumors, resulting in reduced three and five year overall survival rates when compared to surgical resection. Multimodal approaches to include RFA with other standard and investigational approaches have become a subject of recent interest. RFA capably produces cellular destruction causing liberation of a substantial amount of antigens, many of which are tumor-specific providing a favorable environment for immune recognition. We propose that utilizing an immunotherapeutic approach in conjunction with RFA is the next logical step in the treatment of HCC. In this review, we summarize how RFA modulates antitumor immunity and works in concert with immunotherapy in the treatment of HCC. The information provided is expected to help the future design of novel RFA-integrated immunotherapies which are able to generate durable and powerful antitumor immune response to achieve optimal tumor control.

Hepatocellular Carcinoma Patients With Performance Status 1 Deserve New Classification and Treatment Algorithm in the BCLC System

Hepatocellular carcinoma (HCC) patients with performance status (PS) 1 or 2 are considered similar in the Barcelona Clinic Liver Cancer (BCLC) system. The rationales are not fully studied. A total of 693 and 335 HCC patients were classified as PS 1 and 2, respectively, in a prospectively followed up database. One-to-one matched pairs between HCC patients were generated by using the propensity score with matching model. Survival analysis was performed and the hazard ratio was calculated with the Cox proportional hazards model. Patients with PS 1 were significantly younger and had better liver and renal functions compared with patients with PS 2 (all P < 0.05). Patients with PS 1 had earlier BCLC stages and higher chances to undergo curative treatments (both P < 0.05). After matching, patients with PS 1 or 2 had similar age, gender, liver diseases, severity of cirrhosis, tumor burden, and treatments (all P > 0.05); patients with PS 1 had significantly better prognosis compared with patients with PS 2 (P < 0.05). There were 68% of patients with PS 1 that underwent aggressive treatments (resection, transplantation, percutaneous ablation, or transarterial chemoembolization), which were significantly correlated to better outcome with a hazard ratio of 0.539 in the matching model (P = 0.002). For patients with PS 2, aggressive treatments were not significantly associated with better long-term survival. Aggressive treatments provide survival benefits for patients with PS 1, but not for patients with PS 2. HCC patients with PS 1 or 2 should be considered clinically different disease entities in the BCLC system.

Efficacy of perifosine alone and in combination with sorafenib in an HrasG12V plus shp53 transgenic mouse model of hepatocellular carcinoma

PURPOSE

Perifosine has shown antitumor activity via inhibition of Akt phosphorylation in many advanced solid tumors. This study investigated the efficacy of perifosine alone and in combination with sorafenib in a transgenic mouse model of HCC.

METHODS

The mouse model of HCC was generated by hydrodynamic injection of transposons encoding HrasG12V and short-hairpin RNA downregulating p53. The transgenic mice were treated with perifosine alone and in combination with sorafenib to evaluate efficacy of drugs on tumor growth and survival.

RESULTS

Treatment with perifosine for 5 weeks, alone and in combination with sorafenib, strongly inhibited tumor growth and increased survival. Perifosine inhibited HCC cell proliferation, induced apoptosis, and decreased tumor angiogenesis. Furthermore, its combination with sorafenib enhanced these effects. In addition, Akt phosphorylation was decreased by perifosine and further decreased by combination treatment. Although perifosine alone did not appear to activate the caspase pathway, combination treatment increased the cleavage of caspase-3, caspase-9, and poly (ADP-ribose) polymerase.

CONCLUSIONS

The preclinical effect that current study showed represents a strong rationale for clinical trials using perifosine alone and in combination with sorafenib in the treatment of HCC patients.

Yttrium-90 radioembolization vs sorafenib for intermediate-locally advanced hepatocellular carcinoma: a cohort study with propensity score analysis

BACKGROUND & AIMS

Sorafenib and transarterial (90) Y-radioembolization (TARE) are possible treatments for Barcelona Clinic Liver Cancer (BCLC) intermediate-advanced stage hepatocellular carcinoma (HCC). No study directly comparing sorafenib and TARE is currently available. This single-centre retrospective study compares the outcomes achieved with sorafenib and TARE in HCC patients potentially amenable to either therapy.

METHODS

Seventy-four sorafenib (71 ± 10 years, male 87%, BCLC B/C 53%/47%) and 63 TARE HCC patients (66 ± 9 years, male 79%, BCLC B/C 41%/59%) were included based on the following criteria: Child-Pugh class A/B, performance status ≤1, HCC unfit for other effective therapies, no metastases and no previous systemic chemotherapy.

RESULTS

Median overall survivals of the two groups were comparable, being 14.4 months (95% CI: 4.3-24.5) in sorafenib and 13.2 months (95% CI: 6.1-20.2) in TARE patients, with 1-, 2- and 3-year survival rates of 52.1%, 29.3% and 14.7% vs 51.8%, 27.8% and 21.6% respectively. Two TARE patients underwent liver transplantation after successful down-staging. To minimize the impact of confounding factors on survival analysis, propensity model matched 32 patients of each group for median age, tumour gross pathology and the independent prognostic factors (portal vein thrombosis, performance status, Model for End Liver Disease). Even after matching, the median survival did not differ between sorafenib (13.1 months; 95% CI: 1.2-25.9) and TARE patients (11.2 months; 95% CI: 6.7-15.7), with comparable 1-, 2- and 3-year survival rates.

CONCLUSIONS

In cirrhotic patients with intermediate-advanced or not-otherwise-treatable HCC, sorafenib and TARE provide similar survivals. Down-staging allowing liver transplantation only occurred after TARE.

Binding interaction between sorafenib and calf thymus DNA: spectroscopic methodology, viscosity measurement and molecular docking

The binding interaction of sorafenib with calf thymus DNA (ct-DNA) was studied using UV-vis absorption spectroscopy, fluorescence emission spectroscopy, circular dichroism (CD), viscosity measurement and molecular docking methods. The experimental results revealed that there was obvious binding interaction between sorafenib and ct-DNA. The binding constant (Kb) of sorafenib with ct-DNA was 5.6×10(3) M(-1) at 298 K. The enthalpy and entropy changes (ΔH(0) and ΔS(0)) in the binding process of sorafenib with ct-DNA were -27.66 KJ mol(-1) and -21.02 J mol(-1) K(-1), respectively, indicating that the main binding interaction forces were van der Waals force and hydrogen bonding. The docking results suggested that sorafenib preferred to bind on the minor groove of A-T rich DNA and the binding site of sorafenib was 4 base pairs long. The conformation change of sorafenib in the sorafenib-DNA complex was obviously observed and the change was close relation with the structure of DNA, implying that the flexibility of sorafenib molecule played an important role in the formation of the stable sorafenib-ct-DNA complex.

The study of a novel sorafenib derivative HLC-080 as an antitumor agent

In this study, our objective is to evaluate the potential of a novel Sorafenib derivative, named HLC-080, as a new anticancer agent for colon cancer. We firstly carried out MTT assay, colony formation assay, flow cytometry analysis and transwell invasion assay to determine effect of our compound HLC-080 on cell viability, anti-proliferation activity, cell cycle arrest and the intervention on cell invasion, respectively. On the other hand, in vivo antitumor activity of HLC-080 was also tested using H22 xenograft model and the angiogenesis effect of HLC-080 was measured by EA.hy926 tube formation assay. The expression levels of various proteins in HLC-080 treated with HT-29 cell lines were examined using Western blot and ELISA experiments. The results showed that HLC-080 could dramatically inhibit the growth and colony formation of various tumor cells, therefore exhibited remarkable antitumor activity. HLC-080 can induce cell cycle arrest at G1 phase in HT-29 cells and subsequently inhibit the invasive potential of colon cancer cells. HLC-080 also exhibits anti-angiogenesis effect in EA.hy926 model. Additionally, the in vivo study showed that HLC-080 was able to reduced the tumor weight with the rate of 35.81%. And at the concentration of 0.352±0.034 µM, HLC-080 is able to reduce half of the regular protein level of p-c-Raf (Ser259), consequently block Raf/MEK/ERK signaling in HT-29 cell lines. In conclusion, our study suggests that Sorafenib derivative HLC-080 has the potential to inhibit cell proliferation and angiogenesis, Since, HLC-080 is particularly active against human colon cancer cells, our study highlights that HLC-080 and its related analogues may serve as a new anti-cancer drug, particularly against colon cancer.

Isolated fat-containing pancreatic metastasis from hepatocellular carcinoma

We report a case of a 50-year-old male with isolated pancreatic metastasis from hepatocellular carcinoma (HCC), in which chemical shift magnetic resonance imaging detected the presence of fat, and which mimicked fatty replacement. A solitary metastatic pancreatic tumor originating from HCC is very rare. Furthermore, we believe that this is the first report of fat-containing pancreatic metastasis from HCC.

The anti-viral effect of sorafenib in hepatitis C-related hepatocellular carcinoma

BACKGROUND

Sorafenib is currently the only approved systemic therapy shown to have efficacy in the treatment of advanced hepatocellular carcinoma (HCC). Recent studies suggest that hepatitis C (HCV)-related HCC patients derive more clinical benefit from sorafenib than other subgroups, but the mechanism for this effect is unknown. In vitro data suggest that sorafenib may exert anti-viral properties, and thus our aim in this study was to evaluate potential anti-viral activity of sorafenib in patients with HCV-related HCC.

AIM

To evaluate potential anti-viral activity of sorafenib in patients with HCV-related HCC.

METHODS

We prospectively enrolled patients with HCV-related HCC treated with sorafenib for up to 6 months. Baseline clinical, viral and oncologic data were collected. Patients' HCV viral loads were obtained at various time points, and compared with their baseline viral levels. No patients received any known anti-viral therapy during this time.

RESULTS

Thirty-three patients were identified with baseline and subsequent HCV levels available for analysis. Six patients completed 6 months of full dose sorafenib, and comparisons of their HCV viral loads showed no significant change at week 24 (difference of means = 0.3500, CI: -0.1799-0.8799, P = 0.150), or the interim time points. Similarly, the HCV viral loads of all patients who received sorafenib and the viral loads of those patients who had tumour response to sorafenib showed no significant changes at any time point.

CONCLUSION

Despite preclinical data and previous subgroup analyses suggesting that sorafenib has an anti-viral effect against HCV, this study suggests that sorafenib lacks significant anti-viral activity in HCV patients with HCC.

Novel EGFR-TK inhibitor EKB-569 inhibits hepatocellular carcinoma cell proliferation by AKT and MAPK pathways

Epidermal growth factor receptor (EGFR)-targeted therapies have been effective in some cancers, but not in hepatocellular carcinoma (HCC). The aim of this study was to investigate the drug potential to overcome multi-drug resistance in HCC cells. Thirteen drug-sensitive HCC cells were assessed using the CCK-8 assay. G(0)-G(1) arrest was measured by FACS. Western blot analysis was used to detect the key enzymes in both the Ras/Raf and PI3K pathways. When establishing the IC(50) of HCC to several drugs, including EKB-569, sorafenib, erlotinib, gefitinib, pazopanib, and brivanib, SK-Hep1 cells treated with EKB-569 have shown the highest (72.8%-86.4%) G(0)-G(1) arrest and decreased the phosphorylation of AKT and ERK at the protein level. We found that EKB-569 had higher efficacy in HCC, compared to first generation, reversible EGFR-TK inhibitors. Furthermore, the combination of sorafenib and EKB-569 showed a synergistic effect to inhibit proliferation of SNU-475, previously the most resistant cell to EGFR-TKIs. Therefore, novel EKB-569 in combination with sorafenib may be able to overcome HCC resistance to EGFR-TK inhibitors.

PKI-587 and sorafenib targeting PI3K/AKT/mTOR and Ras/Raf/MAPK pathways synergistically inhibit HCC cell proliferation

BACKGROUND

Deregulated Ras/Raf/MAPK and PI3K/AKT/mTOR signaling pathways are found in hepatocellular carcinoma (HCC). This study aimed to test the inhibitory effects of PKI-587 and sorafenib as single agents or in combination on HCC (Huh7 cell line) proliferation.

MATERIALS AND METHODS

(3)H-thymidine incorporation and MTT assay were used to assess Huh7 cell proliferation. Phosphorylation of the key enzymes in the Ras/Raf/MAPK and PI3K/AKT/mTOR pathways was detected by Western blot.

RESULTS

We found that PKI-587 is a more potent PI3K/mTOR inhibitor than PI-103. Combination of PKI-587 and sorafenib was a more effective inhibitor of Huh7 proliferation than the combination of PI-103 and sorafenib. Combination of PKI-587 and sorafenib synergistically inhibited epidermal growth factor (EGF)-stimulated Huh7 proliferation compared with monodrug therapy. EGF increased phosphorylation of Ras/Raf downstream signaling proteins MEK and ERK; EGF-stimulated activation was inhibited by sorafenib. However, sorafenib, as a single agent, increased AKT (Ser473) phosphorylation. EGF-stimulated AKT (ser473) activation was inhibited by PKI-587. PKI-587 is a potent inhibitor of AKT (Ser473), mTOR (Ser2448), and S6K (Thr389) phosphorylation; in contrast, rapamycin stimulated mTOR complex 2 substrate AKT(Ser473) phosphorylation although it inhibited mTOR complex 1 substrate S6K phosphorylation. PKI-587, as a single agent, stimulated MEK and ERK phosphorylation. However, when PKI-587 and sorafenib were used in combination, they inhibited all the tested kinases in the Ras/Raf /MAPK and PI3K/AKT/mTOR pathways.

CONCLUSION

The combination of PKI-587 and sorafenib has the advantage over monodrug therapy on inhibition of HCC cell proliferation by blocking both PI3K/AKT/mTOR and Ras/Raf/MAPK signaling pathways.

Safety and efficacy of sorafenib in hepatocellular carcinoma: the impact of the Child-Pugh score

BACKGROUND

Sorafenib increases median survival and time to radiological progression in patients with advanced hepatocellular carcinoma, but its benefit for Child-Pugh B patients remains uncertain.

AIM

To evaluate the safety and efficacy of sorafenib in real-life clinical practice conditions and to assess the influence of Child-Pugh class B on safety and efficacy.

METHODS

All patients treated with sorafenib for advanced hepatocellular carcinoma in our institution were included prospectively. Adverse events, overall survival and time to progression were recorded. A case control study was performed to compare outcome of patients with comparable stages of hepatocellular carcinoma, but a different Child-Pugh class.

RESULTS

From March 2007 to May 2009, 120 patients were included. Overall survival was 11.1 months, Child-Pugh A patients (n=100) had significantly higher median survival than Child-Pugh B patients (n=20) (13 vs. 4.5 months, P=0.0008). In multivariate analysis, Child-Pugh class B, α-fetoprotein level and total size of lesions were independent predictive factors of death. Patients with radiological progression in the first 3 months had shorter median survival (5.4 vs. 17.4 months). In a case control study, time to symptomatic progression (2.5 vs. 3.6 months), frequency of adverse events and discontinuation of sorafenib were not correlated with Child-Pugh class.

CONCLUSIONS

Patients with advanced hepatocellular carcinoma treated with sorafenib had a median survival of 11 months. Sorafenib therapy must be considered with caution in Child-Pugh B patients due to their poor survival. Radiological assessment of tumour progression at an early stage may be advantageous when tailoring sorafenib therapy.

Molecular targets and oxidative stress biomarkers in hepatocellular carcinoma: an overview

Hepatocellular carcinoma (HCC) is a complex and heterogeneous tumor with multiple genetic aberrations. Several molecular pathways involved in the regulation of proliferation and cell death are implicated in the hepatocarcinogenesis. The major etiological factors for HCC are both hepatitis B virus (HBV) and hepatitis C virus infection (HCV). Continuous oxidative stress, which results from the generation of reactive oxygen species (ROS) by environmental factors or cellular mitochondrial dysfunction, has recently been associated with hepatocarcinogenesis. On the other hand, a distinctive pathological hallmark of HCC is a dramatic down-regulation of oxido-reductive enzymes that constitute the most important free radical scavenger systems represented by catalase, superoxide dismutase and glutathione peroxidase. The multikinase inhibitor sorafenib represents the most promising target agent that has undergone extensive investigation up to phase III clinical trials in patients with advanced HCC. The combination with other target-based agents could potentiate the clinical benefits obtained by sorafenib alone. In fact, a phase II multicenter study has demonstrated that the combination between sorafenib and octreotide LAR (So.LAR protocol) was active and well tolerated in advanced HCC patients. The detection of molecular factors predictive of response to anti-cancer agents such as sorafenib and the identification of mechanisms of resistance to anti-cancer agents may probably represent the direction to improve the treatment of HCC.

Prognostic factors in patients with advanced hepatocellular carcinoma treated with sorafenib

BACKGROUND

Sorafenib is the new reference standard for patients with advanced hepatocellular carcinoma (HCC).

AIM

To identify prognostic factors in sorafenib-treated HCC patients and to evaluate outcomes with respect to liver function.

METHODS

In this retrospective study, 148 HCC patients received sorafenib 400 mg b.d. across 11 Austrian institutions. Seventy-eight HCC patients who received best supportive care (BSC) in the pre-sorafenib era served as a control.

RESULTS

In sorafenib-treated patients, low baseline α-fetoprotein, low Child-Pugh (CP) score, compensated cirrhosis, and low baseline aspartate aminotransferase (AST) were associated with significantly longer overall survival (OS) on univariate analysis. CP score and baseline AST remained independent prognostic factors on multivariate analysis. In patients with Barcelona Clinic liver Cancer (BCLC) stage B or C HCC (sorafenib: n = 139; BSC: n = 39), CP-A patients had a median OS of 11.3 (sorafenib [n = 76]) vs. 6.4 (BSC [n = 17]) months (P = 0.010), and CP-B patients had a median OS of 5.5 (sorafenib [n = 55]) vs. 1.9 (BSC [n = 22]) months (P = 0.021). In the sorafenib group, median OS according to baseline AST was 11.8 (<100 U/L [n = 58]) vs. 3.9 (≥100 U/L [n = 15]) months for CP-A patients (P = 0.127), and 6.5 (<100 U/L [n = 33]) vs. 2.1 (≥100 U/L [n = 21]) months for CP-B patients (P = 0.011). There was no survival difference between sorafenib and BSC in patients with BCLC stage D HCC (1.5 vs. 1.4 months; P = 0.116).

CONCLUSIONS

Sorafenib was associated with improved survival in both CP-A and CP-B patients. In CP-B patients, baseline AST may be helpful in determining which patients are most likely to benefit from sorafenib.

The combination of sorafenib with transarterial chemoembolisation for hepatocellular carcinoma

BACKGROUND

Standard of practice involves using transarterial therapy for multifocal hepatocellular carcinoma (HCC) alone and sorafenib only for more advanced HCC, but the sorafenib and transarterial therapy combination may provide greater efficacy.

AIM

To evaluate the safety and efficacy of concurrent sorafenib and transarterial therapy in HCC.

METHODS

Consecutive cases of HCC were treated with sorafenib and transarterial therapy, receiving sorafenib 2 to 4weeks before transarterial therapy. Baseline clinical parameters, adverse events (AEs) and survival were collected.

RESULTS

A total of 47 patients received sorafenib and transarterial therapy. The majority of the patients were male (70%) with HCV (60%), median age of 60years, good performance status (0-1), stable cirrhosis (Child: A 72%; B 28%), unresectable tumour (stage: B 81%; C 19%) and median AFP of 24ng/mL. Median follow-up was 12months and median time on sorafenib was 6months. LC Bead TACE was used with a median frequency of 3. The majority of the patients (89%) experienced AEs. The most common AEs were fatigue (51%), hand-foot skin reaction (51%) and diarrhoea (43%). Grade 3 and 4 AEs included fatigue (13%) and hand-foot skin reaction (26%). Most patients required a dose reduction (66%). The main AE related to transarterial therapy was post-TACE syndrome (23%). The disease control rate was 68% at 6months. Overall median survival rate was 18.5months (95% CI 16.1-20.9months).

CONCLUSION

Concurrent sorafenib and transarterial therapy is overall safe with no unexpected side effects and encouraging efficacy that warrants further study.

Outcome of supraselective transarterial chemoembolization in patients with hepatocellular carcinoma

OBJECTIVE

Hepatocellular carcinoma (HCC) is the most common tumor in cirrhotic patients with a median survival of only 8-10 months if untreated. Supraselective transarterial chemoembolization (STACE) is supposed to be a well-established method for treating HCC patients. In the present study, we evaluated the effect of STACE on post-transplant survival in patients with HCC.

MATERIAL AND METHODS

The charts of 53 HCC patients were retrospectively analyzed. Twenty-seven patients had STACE as a bridging therapy while 26 patients were scheduled for liver transplantation (LTX) without prior STACE therapy. A total of 53% of the patients who underwent LTX preoperatively fulfilled the Milan criteria, while 70.6% fulfilled the expanded University of California, San Francisco (UCSF) transplant criteria. Primary endpoint was the post-transplant survival. Statistical analysis included Kaplan-Meier-method, log rank, and chi square tests.

RESULTS

Between the LTX groups (STACE vs. non-STACE), there was no significant difference in terms of age, Child classification, Okuda stage, co-morbidities, underlying disease, and post-transplant survival (p > 0.05). Independent of prior STACE, however, disease-free survival after LTX was highly significantly prolonged if LTX was performed within 3 months after initial diagnosis of HCC (p < 0.01) or if patients met the expanded transplant UCSF criteria (p = 0.02). Post-transplant survival did not depend on tumor size.

CONCLUSIONS

We conclude that STACE performed prior to LTX does not secure any post-transplant survival benefit, while early LTX, i.e. within 3 months after HCC diagnosis, does improve survival regardless of whether STACE was performed or not. Additionally, fulfillment of the expanded transplant UCSF criteria leads to a prolonged post-transplant survival.

Pilot study: rapamycin in advanced hepatocellular carcinoma

BACKGROUND

The PI3K/Akt/mTOR signal pathway is involved in hepatocarcinogenesis. Rapamycin (=sirolimus), a specific mTOR inhibitor, leads to G(1) arrest of many malignant cell lines and currently, analogues of rapamycin are being investigated as a cancer chemotherapeutic adjuvant.

AIM

To study the toxicity and tolerability of rapamycin therapy in patients with advanced hepatocellular carcinoma (HCC).

METHODS

Between June 2005 and February 2007, patients with advanced HCC, not eligible for any established therapy, were included in the study.

RESULTS

Eighteen patients (F/M: 5/13) with compensated liver cirrhosis (Child A n = 11, Child B n = 5, Child C n = 2) and histologically proven HCC were included in this study. According to the BCLC staging system, most of the patients enrolled had an advanced HCC: BCLC stage B: n = 2, Barcelona Clinic Liver-Cancer (BCLC) stage C: n = 14, BCLC stage D: n = 2. Overall, therapy with rapamycin was well tolerated. Most common toxicities were thrombocytopaenia and anaemia. We did not observe any partial or complete tumour response. At 3 months, two patients had stable disease and at 6 months, all patients had progressed. The median overall survival was 5.27 months, median time to progression was 3 months.

CONCLUSION

Rapamycin is well tolerated in patients with advanced HCC, but only minimally effective.

Hepatocellular carcinoma: consensus recommendations of the National Cancer Institute Clinical Trials Planning Meeting

Hepatocelluar carcinoma (HCC) is the most common primary malignancy of the liver in adults and the third most common cause of cancer death worldwide. The incidence of HCC in the United States is rising steadily because of the prevalence of hepatitis C viral infection and other causes of hepatic cirrhosis. The majority of patients have underlying hepatic dysfunction, which complicates patient management and the search for safe and effective therapies. The Clinical Trials Planning Meeting (CTPM) in HCC was convened by the National Cancer Institute's Gastrointestinal Cancer Steering Committee to identify the key knowledge gaps in HCC and define clinical research priorities. The CTPM structured its review according to current evidence-based treatment modalities in HCC and prioritized the recommendations on the basis of the patient populations representing the greatest unmet medical need.

TRAIL-induced apoptosis of hepatocellular carcinoma cells is augmented by targeted therapies

AIM: To analyze the effect of chemotherapeutic drugs and specific kinase inhibitors, in combination with the death receptor ligand tumor necrosis factor-related apoptosis inducing ligand (TRAIL), on overcoming TRAIL resistance in hepatocellular carcinoma (HCC) and to study the efficacy of agonistic TRAIL antibodies, as well as the commitment of antiapoptotic BCL-2 proteins, in TRAIL-induced apoptosis.

METHODS: Surface expression of TRAIL receptors (TRAIL-R1-4) and expression levels of the antiapoptotic BCL-2 proteins MCL-1 and BCL-x_L were analyzed by flow cytometry and Western blotting, respectively. Knock-down of MCL-1 and BCL-x_L was performed by transfecting specific small interfering RNAs. HCC cells were treated with kinase inhibitors and chemotherapeutic drugs. Apoptosis induction and cell viability were analyzed via flow cytometry and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.

RESULTS: TRAIL-R1 and -R2 were profoundly expressed on the HCC cell lines Huh7 and Hep-G2. However, treatment of Huh7 and Hep-G2 with TRAIL and agonistic antibodies only induced minor apoptosis rates. Apoptosis resistance towards TRAIL could be considerably reduced by adding the chemotherapeutic drugs 5-fluorouracil and doxorubicin as well as the kinase inhibitors LY294002 [inhibition of phosphoinositol-3-kinase (PI3K)], AG1478 (epidermal growth factor receptor kinase), PD98059 (MEK1), rapamycin (mammalian target of rapamycin) and the multi-kinase inhibitor Sorafenib. Furthermore, the antiapoptotic BCL-2 proteins MCL-1 and BCL-x_L play a major role in TRAIL resistance: knock-down by RNA interference increased TRAIL-induced apoptosis of HCC cells. Additionally, knock-down of MCL-1 and BCL-x_L led to a significant sensitization of HCC cells towards inhibition of both c-Jun N-terminal kinase and PI3K.

CONCLUSION: Our data identify the blockage of survival kinases, combination with chemotherapeutic drugs and targeting of antiapoptotic BCL-2 proteins as promising ways to overcome TRAIL resistance in HCC.

Identifying drug effects via pathway alterations using an integer linear programming optimization formulation on phosphoproteomic data

Understanding the mechanisms of cell function and drug action is a major endeavor in the pharmaceutical industry. Drug effects are governed by the intrinsic properties of the drug (i.e., selectivity and potency) and the specific signaling transduction network of the host (i.e., normal vs. diseased cells). Here, we describe an unbiased, phosphoproteomic-based approach to identify drug effects by monitoring drug-induced topology alterations. With our proposed method, drug effects are investigated under diverse stimulations of the signaling network. Starting with a generic pathway made of logical gates, we build a cell-type specific map by constraining it to fit 13 key phopshoprotein signals under 55 experimental conditions. Fitting is performed via an Integer Linear Program (ILP) formulation and solution by standard ILP solvers; a procedure that drastically outperforms previous fitting schemes. Then, knowing the cell's topology, we monitor the same key phosphoprotein signals under the presence of drug and we re-optimize the specific map to reveal drug-induced topology alterations. To prove our case, we make a topology for the hepatocytic cell-line HepG2 and we evaluate the effects of 4 drugs: 3 selective inhibitors for the Epidermal Growth Factor Receptor (EGFR) and a non-selective drug. We confirm effects easily predictable from the drugs' main target (i.e., EGFR inhibitors blocks the EGFR pathway) but we also uncover unanticipated effects due to either drug promiscuity or the cell's specific topology. An interesting finding is that the selective EGFR inhibitor Gefitinib inhibits signaling downstream the Interleukin-1alpha (IL1alpha) pathway; an effect that cannot be extracted from binding affinity-based approaches. Our method represents an unbiased approach to identify drug effects on small to medium size pathways which is scalable to larger topologies with any type of signaling interventions (small molecules, RNAi, etc). The method can reveal drug effects on pathways, the cornerstone for identifying mechanisms of drug's efficacy.

Sorafenib: a review of its use in advanced hepatocellular carcinoma

Sorafenib (Nexavar) is an orally active multikinase inhibitor that is approved in the EU for the treatment of hepatocellular carcinoma. Monotherapy with sorafenib prolongs overall survival and delays the time to progression in patients with advanced hepatocellular carcinoma who are not candidates for potentially curative treatment or transarterial chemoembolization. Sorafenib is generally well tolerated in patients with advanced hepatocellular carcinoma. Thus, sorafenib represents an important advance in the treatment of advanced hepatocellular carcinoma and is the new standard of care for this condition. The bi-aryl urea sorafenib is an oral multikinase inhibitor that inhibits cell surface tyrosine kinase receptors (e.g. vascular endothelial growth factor receptors and platelet-derived growth factor receptor-beta) and downstream intracellular serine/threonine kinases (e.g. Raf-1, wild-type B-Raf and mutant B-Raf); these kinases are involved in tumour cell proliferation and tumour angiogenesis. In vitro, dose-dependent inhibition of cell proliferation and induction of apoptosis was seen with sorafenib in human hepatocellular carcinoma cells lines. Sorafenib demonstrated dose-dependent antitumour activity in a murine xenograft model of human hepatocellular carcinoma. Steady-state plasma concentrations were reached within 7 days in patients with advanced, refractory solid tumours who received twice-daily oral sorafenib. Metabolism of sorafenib occurs primarily in the liver and is mediated via cytochrome P450 (CYP) 3A4 and uridine diphosphate glucuronosyltransferase 1A9. In advanced hepatocellular carcinoma, differences in sorafenib pharmacokinetics between Child-Pugh A and B patients were not considered clinically significant. Sorafenib may be associated with drug interactions. For example, sorafenib exposure was reduced by an average 37% with concomitant administration of the CYP3A4 inducer rifampicin (rifampin); sorafenib concentrations may also be decreased by other CYP3A4 inducers. Monotherapy with oral sorafenib 400 mg twice daily prolonged median overall survival and delayed the median time to progression in patients with advanced hepatocellular carcinoma, according to the results of two randomized, double-blind, placebo-controlled, multicentre, phase III trials (the SHARP trial and the Asia-Pacific trial). There was no significant difference between sorafenib and placebo recipients in the median time to symptomatic progression in either trial. The vast majority of patients included in these trials were Child-Pugh A. Combination therapy with sorafenib plus doxorubicin did not delay the median time to progression to a significant extent compared with doxorubicin alone in patients with advanced hepatocellular carcinoma, according to the results of a randomized, double-blind, phase II trial. However, the median durations of overall survival and progression-free survival were significantly longer in patients receiving sorafenib plus doxorubicin than in those receiving doxorubicin alone. Combination therapy with sorafenib plus tegafur/uracil or mitomycin also showed potential in advanced hepatocellular carcinoma, according to the results of noncomparative trials. Monotherapy with oral sorafenib was generally well tolerated in patients with advanced hepatocellular carcinoma, with a manageable adverse effect profile; diarrhoea and hand-foot skin reaction were consistently the most commonly occurring drug-related adverse events in clinical trials. In the SHARP trial, drug-related adverse events of any grade occurring in significantly more sorafenib than placebo recipients included diarrhoea, hand-foot skin reaction, anorexia, alopecia, weight loss, dry skin, abdominal pain, voice changes and 'other' dermatological events. A similar tolerability profile was seen in the Asia-Pacific trial. As expected given the addition of a chemotherapy agent, the adverse event profile in patients with advanced hepatocellular carcinoma who received combination therapy with sorafenib plus doxorubicin differed somewhat to that seen with sorafenib monotherapy in the SHARP trial. In patients receiving sorafenib plus doxorubicin, the most commonly occurring all-cause adverse events (all grades) included fatigue, neutropenia, diarrhoea, elevated bilirubin levels, abdominal pain, hand-foot skin reaction, left ventricular dysfunction, hypertension and febrile neutropenia.